Thy kind favor, of Apr 17. 16, had been forwarded from Brookeville to this place, my present residence, during a second journey I have made to Washington City. I returned yesterday.

While in the Metropolis, I conceived an expectation, which1 still exists, of an employment either in the survey of the line between the United States and the British possessions, from the source of St Croix to the river St Lawrence, or in the Survey of the coast—Or if these surveys should be so organised as to place the scientific operations under the special direction of one person to be stationed at some central point, to and from which the communication would be easy; this director to receive the notes and make all the calculations and maps—at my age, I should prefer such a station, leaving to younger men the more active and laborious operations of tracing lines and measuring bases, of taking angles and making astronomical observations. By the time this letter reaches thee, I expect our friend James Madison will be at Montpelier, I should be glad if thou and he could converse on the subject, and what you think best for me, that do—what you think best for our country, I am sure you will do.

I thank thee feelingly for thy wishes to engage me in the survey of Virginia—the circumstance of its bringing me often near to thee in body as I always am in mind, inclines me to it strongly; but whatever thou dost for me, I believe I shall think best.

I wish much for a careful examination of the ground between the nearest waters of James River and of the Cheat River—and between the nearest waters of the Potomak and of the Monongahela, as to its level, with a view to a future navigation across the Alegany mountains. I believe most firmly such a navigation is practicable, and that the consequences of it would be of great national importance.

I will consider with my best attention thy astronomical problem, and in a future communication, state the result.